Fluids in the continental crust: decrypting geological processes using noble gases

该研究项目将重点研究岩石圈中流体的起源和演化，以及它们在大陆地壳地球动力学演化中所起的关键作用。它将解决以下基本问题：1)地层间流体流动的持续时间和长度及其在地壳脱气中的作用；Ii)古水的存在是大陆地壳演化的地质档案；（三）具有经济价值的地壳流体，特别是地热流体和页岩气的成因和演化。****为了实现这些目标，将在不同空间和时间尺度的沉积和热液环境中开展一系列项目。一些重点将放在负责含水层中气态物种（甲烷，氦）垂直迁移的过程，以及大陆上渗漏的成因，自然实验室是圣劳伦斯低地（QC）。研究的目的是量化甲烷通量，并模拟从尤蒂卡页岩输送甲烷的过程。这些模型将被应用于寻求致密气开采的Anticosti岛。将探索的另一个重要方面是在Abitibi-Temiscamingue的Cadillac断裂的深部采矿环境中存在数亿至数十亿年历史的流体及其在成矿作用中的作用。与NSERC的研究计划并行，我们正在对墨西哥最大的活跃地热系统中热液流体的演化进行详细研究，以评估它们的寿命和发电能力。这些热液环境是化石浅成热液矿床的现代模拟物。将获得的大型化学和同位素数据库对于了解这些环境中金属和流体来源之间的关系至关重要，这是未来矿石成因模型的前提。我们正在发展的关于地热系统的大量和独特的专门知识也将应用于对加拿大一些省份的地热能力的研究，特别是班夫地热区的成因。****追踪这些“地流体”的起源和演化的方法方法是基于保守元素的同位素，即惰性气体，对此我在加拿大具有独特的专业知识。惰性气体具有化学惰性、稀少性，且产自同位素不同的储层，是理想的流体示踪剂。有几种同位素是放射性衰变的产物，这为在几年到数十亿年的时间尺度上测定流体的年代提供了机会。****该研究项目为年轻的HQP提供了一个独特的机会，可以在大陆地壳水循环及其动态（行为）研究中获得多学科的科学，分析和专业经验，同时专攻稀有气体地球化学这一具有挑战性和回报的科学学科

The research program will focus on the origin and evolution of fluids in the lithosphere and the critical role they play in the geodynamical evolution of the continental crust. It will address fundamental questions about i) the duration and length of cross-formational fluid flow and its role in the crustal degassing; ii) the existence of fossil water as geological archives of the continental crust evolution; iii) the genesis and evolution of crustal fluids of economic interest, particularly geothermal fluids and shale gas.****To meet these objectives, a series of projects will be undertaken in sedimentary and hydrothermal environments - at different spatial and temporal scales. Some focus will be put on the processes responsible for vertical migration of gaseous species (methane, helium.) in aquifers, and the genesis of seepage on continents, with natural laboratory being the St. Lawrence Lowlands (QC). Studies will be aimed at quantifying methane fluxes and model the process of transport from Utica shale. These models will be translated to the Island of Anticosti where tight gas exploitation is sought. Another important aspect that will be explored is the occurrence of hundreds millions to billions years old fluids in deep mining environments and their role in mineralization along the Cadillac fault in Abitibi-Temiscamingue. Parallel to this NSERC research program, we are carrying out a detailed study of the evolution of hydrothermal fluids in the largest active geothermal systems of Mexico in order to assess their lifetime and power capacities. These hydrothermal environments are the modern analogue of the fossil epithermal ore deposits. The large chemical and isotopic database that will be acquired will be crucial to understand the relation between metals and fluid sources in these environments, a premise to future ore genesis models. The tremendous and unique expertise we are developing on geothermal systems will be also applied to the study of the geothermal capacity of some Canadian Provinces, in particular the genesis of the Banff's geothermal area.****The methodological approach to trace the origin and evolution of these "geofluids" is based on the isotopes of conservative elements, namely noble gases, for which I have a unique expertise in Canada. Being chemically inert, scarce and sourced from isotopically distinct reservoirs, noble gases are ideal fluid tracers. Several isotopes are products of radioactive decay, opening opportunities of dating fluids on timescales going to a few years to billions of years.****This research program represents a unique opportunity for young HQP to acquire a multi-disciplinary scientific, analytical and professional experience, in the study of the water cycle and its dynamic (behavior) in the continental crust, while specializing in a challenging and rewarding scientific discipline that is the noble gas geochemistry.**